Klondike - 16 chip ASIC Open Source Board - Preliminary

[marto74]

So 35 x 165 is the standard profile.
The heat sink dimension machined are 80 x 90 mm 35 mm high.
The price is including machining and raw material . Machining : drilled holes, countersinks for clamping springs, surface machining on mating area and power connector release .
To provide cad (parasolid and dwg/dxf) i need PCB cad transferred to dxf or any machining cad
 I got it

[erk]

yes i can get 500mm x 100mm heatsinks as well.
Up to 1.000mm length.

Heatsink



Tell me prefered size and send me the hole patterns and i will manufacture you a sample.

Thats a good size, Avalon mount 8 x 10 chip boards on the same heats sink which is long but still fits in something like a PC case depth ok.

[BkkCoins]

I've just updated the K16 board to use 4mm holes, and have another KLego connector on the back edge.

I wanted users to be able to use common ATX motherboard parts for mounting and according to the docs for that they use 0.156", which is just slightly under 4mm. Also this should work with a #6-32 bolt which I think is a bit better than smaller #4 ones.

Thanks to steamboat (working hard on getting USA assembly together) who pointed out that if heat fins run in one direction then it wouldn't be good with boards tiling in perpendicular orientations. Side-Front etc. This is the reason for the Klego connect at back. Now suggest only tiling in Side-Side and Back-Front orientations. Front to Front may be possible as I left an extra set of pads on the front edge, but it's unnecessary and probably that connector won't be installed to keep BOM the same.
(Front means the edge with USB)

Also moved Power LED so that when tiled Front-Front the Fan connector won't cover it up.
Also moved USB connector back slightly so it doesn't hang over board edge.

A bunch of slight improvements I'm happy to catch before first boards ordered.

Docs, Images and Plots just pushed to github.

[mike2kt]

I wanted users to be able to use common ATX motherboard parts for mounting and according to the docs for that they use 0.156", which is just slightly under 4mm. Also this should work with a #6-32 bolt which I think is a bit better than smaller #4 ones.

Nice!!  So what’s the distance between the new drill points (center point to center point)?   

 

[Bicknellski]

Found this stencil drawing... might be useful for us.

[BkkCoins]

I wanted users to be able to use common ATX motherboard parts for mounting and according to the docs for that they use 0.156", which is just slightly under 4mm. Also this should work with a #6-32 bolt which I think is a bit better than smaller #4 ones.

Nice!!  So what’s the distance between the new drill points (center point to center point)?   

 

Their position hasn't changed just the hole diameter.

ASIC holes are 62mm x 55mm.
Thermal Pads outer edge coverage is 90mm x 80mm.
Corner holes are 90mm x 90mm.

[Bicknellski]

Just to put a bad diagram to your plans for Klego's.... which orientation are you thinking again a vertical or horizontal arrangement?

Fans at the end of either end of the tunnel would work in either arrangement. The horizontal version can fit in side a rack mount 19" wide I believe. The horizontal version would also less prone to heating I think given the density.

[BkkCoins]

Found this stencil drawing... might be useful for us.

It's not quite the same but it's close. The Avalon chip has a 5.4 x 5.4mm pad.
I've placed the vias a bit more spread out but still within the pad, and used the recommended 3x3 paste pattern to prevent "floating".

[BkkCoins]

Just to put a bad diagram to your plans for Klego's.... which orientation are you thinking again a vertical or horizontal arrangement?

Fans at the end of either end of the tunnel would work in either arrangement. The horizontal version can fit in side a rack mount 19" wide I believe. The horizontal version would also less prone to heating I think given the density.

I think either should work but I'd leave more space between the boards. You want air flowing there as well to cool the upper surface and components. At least double would be my guess but the PCIe connector height is about 12mm anyway. So that means 24mm if using horizontal conns. and more if using vertical. Horz. makes more sense for this arrangement.

The Phoenix connectors are not as high and don't require holes sunk in the heat sink for pin spacing. 5mm high each I believe, and they're staggered so would sit side by side if facing each other.. I haven't used these and I don't really know how well the wires connect, but I will get a few for testing.

The upper surface needs colling because there are components other than the ASIC, though it also needs some air flow there. The power inductors and voltage regs need a bit of loving airflow.

BTW the PCIe pins would extend beyond board bottom by about 2mm - for the purpose of sinking holes in the heat sink I would think 3mm should work.

[Bicknellski]

I think trying to stuff some K16s / K64s into existing server or mod PC cases might be the right move for those wanting a "finished" unit. I think like other FPGA's rigs you can also  simply stanchion the boards and pop a fan array on one end or put the fans right on top of the heat sink pushing air right into the fins on each of the heat sinks like the Cairnsmores or even the X6500's.

Given the many options available and the size of the K16 / K64 you are not limited in anyway really. I am keen on seeing what others come up with. I will take those notes BKKCoins and see what off the shelf products are workable.

 

It would be cool if there is a back plane design that has hot swap functionality. You could probably easily retro fit some HDD racks with the back plan so you can plug in the K16s in a single push then the whole unit with 2 or 3 K16's can be mounted right into a PC case.

[BkkCoins]

It would be cool if there was a back plane design that was had hot swap functionality. You could probably easily retro fit some HDD racks with the back plan so you can plug in the K16s in a single push then the whole unit with 2 or 3 K16's can be mounted right into a PC case.

SATA Power connectors are a possible choice, maybe even better than Phoenix for a back edge design. They are hot swap, and SMD so no pin thru. But they are harder to source. Nice that most ATX PSU have a bunch of them.



And nice that they have 3.3V so could actually remove one buck regulator, if I just supported that. It does handle enough current however. If I could mount a SATA connector on the back edge it would connect like a hard disk, and the height would be reduced, and cabling made easier even than PCIe. So there is several advantages.

Hmmm.

Note that Molex to SATA adapters wouldn't work as they often don't have the 3.3V line. But even my modest 600W Corsair has 6 SATA power conns vs. only 2 PCIe conns. and they're spaced about the right distance for these boards in a chain.

[Chefnet]

It would be cool if there was a back plane design that was had hot swap functionality. You could probably easily retro fit some HDD racks with the back plan so you can plug in the K16s in a single push then the whole unit with 2 or 3 K16's can be mounted right into a PC case.

SATA Power connectors are a possible choice, maybe even better than Phoenix for a back edge design. They are hot swap, and SMD so no pin thru. But they are harder to source. Nice that most ATX PSU have a bunch of them.

http://en.wikipedia.org/wiki/File:SATA_power_cable.jpg

And nice that they have 3.3V so could actually remove one buck regulator, if I just supported that. It does handle enough current however. If I could mount a SATA connector on the back edge it would connect like a hard disk, and the height would be reduced, and cabling made easier even than PCIe. So there is several advantages.

Hmmm.

+1

[r3animation]

I think trying to stuff some K16s / K64s into existing server or mod PC cases might be the right move for those wanting a "finished" unit. I think like other FPGA's rigs you can also  simply stanchion the boards and pop a fan array on one end or put the fans right on top of the heat sink pushing air right into the fins on each of the heat sinks like the Cairnsmores or even the X6500's.

Given the many options available and the size of the K16 / K64 you are not limited in anyway really. I am keen on seeing what others come up with. I will take those notes BKKCoins and see what off the shelf products are workable.

 

It would be cool if there is a back plane design that has hot swap functionality. You could probably easily retro fit some HDD racks with the back plan so you can plug in the K16s in a single push then the whole unit with 2 or 3 K16's can be mounted right into a PC case.

+1

I like the idea of this but wouldn't Klondike then need a re-design of the board due to the size contraints?

[erk]

I think trying to stuff some K16s / K64s into existing server or mod PC cases might be the right move for those wanting a "finished" unit. I think like other FPGA's rigs you can also  simply stanchion the boards and pop a fan array on one end or put the fans right on top of the heat sink pushing air right into the fins on each of the heat sinks like the Cairnsmores or even the X6500's.

Given the many options available and the size of the K16 / K64 you are not limited in anyway really. I am keen on seeing what others come up with. I will take those notes BKKCoins and see what off the shelf products are workable.

 

It would be cool if there is a back plane design that has hot swap functionality. You could probably easily retro fit some HDD racks with the back plan so you can plug in the K16s in a single push then the whole unit with 2 or 3 K16's can be mounted right into a PC case.

+1

I like the idea of this but wouldn't Klondike then need a re-design of the board due to the size contraints?

Hmm looks a bit overkill for a 30watt board.

[crazyates]

It would be cool if there was a back plane design that was had hot swap functionality. You could probably easily retro fit some HDD racks with the back plan so you can plug in the K16s in a single push then the whole unit with 2 or 3 K16's can be mounted right into a PC case.

SATA Power connectors are a possible choice, maybe even better than Phoenix for a back edge design. They are hot swap, and SMD so no pin thru. But they are harder to source. Nice that most ATX PSU have a bunch of them.



And nice that they have 3.3V so could actually remove one buck regulator, if I just supported that. It does handle enough current however. If I could mount a SATA connector on the back edge it would connect like a hard disk, and the height would be reduced, and cabling made easier even than PCIe. So there is several advantages.

Hmmm.

Note that Molex to SATA adapters wouldn't work as they often don't have the 3.3V line. But even my modest 600W Corsair has 6 SATA power conns vs. only 2 PCIe conns. and they're spaced about the right distance for these boards in a chain.

Even high-end PSUs will only carry 25-30A on the 3.3V line, which is only good for 80-100W. How much power would each board draw from the 3.3V line?

[BkkCoins]

Even high-end PSUs will only carry 25-30A on the 3.3V line, which is only good for 80-100W. How much power would each board draw from the 3.3V line?

Very little power is used off 3.3V. The SATA conn. also has 12V and 5V on it.
The real problem is that 15pin connectors are impossible to find. So it would have to have the huge 15+7 pin connector but not using the 7 data pins. Right now this is too wide to fit with the ASICs in their current location.

I recall now looking into this on my first day as I thought SATA power would be ideal. But when I found that no one makes a power-only connector I had to switch to PCIe instead. It would be much easier to connect multiple Klondikes to an ATX supply using SATA as you could avoid PCIe splitters.

One option would be a SATA pigtail wired to the board edge hanging off about 4-6 inches. There are male SATA 15pin connectors but only with wire tails.

SATA has 3x 12V pins that can handle 1.5A each, which is enough but not excessive.
Need about ~< 3A @ 12V and < 1 @ 3.3V.

[erk]

I recall now looking into this on my first day as I thought SATA power would be ideal. But when I found that no one makes a power-only connector I had to switch to PCIe instead. It would be much easier to connect multiple Klondikes to an ATX supply using SATA as you could avoid PCIe splitters.

I think PCIe is better as sata is designed for hard drives, not much power required, and PCIe for power hungry video cards. Both are on the standard ATX PSU. The SATA pins are only rated at 1.5A each. The PCIe 6pin 75watts, 8pin 150watts.

[MbaseCNC]

Hi BkkCoins,

I have been following this thread for a while now, is there any chance that you will also post the schematics?
The KiCAD files are nice but somewhat hard to read, like you I'm also a Eagle user.
Thanks

[mike2kt]

I'm in the PCIe camp, but that is mostly because I plan to run 768+ chips. If pulling power off the SATA connector, absolutely use the 12v source (forget about the 3.3v). On the X6500 we found using 12v made a big difference on the board stability. It’s one of those “don’t get cheap”/penny wise pound foolish decisions.

As for the PSU, depends on the unit. Split 12V rails may be an issue...or not for PSUs that have one 12V rail. READ: A Pain in the Asterisk to Support.

[mike2kt]

Hi BkkCoins,

I have been following this thread for a while now, is there any chance that you will also post the schematics?
The KiCAD files are nice but somewhat hard to read, like you I'm also a Eagle user.
Thanks

Even better...I wish Avalon would release ALL the Altium project files. not a lot of fun having to go back and recreate the component library. /whine